In semiconductor device fabrication, back-end-of-line (BEOL) wafer processing generally involves creating various interconnecting metal layers that may be interconnected by vias. Wire bonding pads or pad interconnects are connected to the interconnects and are used to connect an integrated circuit (IC) to other ICs or electronic devices. Wire bonds are attached to the wire bonding pads. The wire bonds may include, for example, gold or copper materials. For example, copper wire bonds may be used more commonly due to its low cost.
However, the environmental conditions may influence the performance and reliability of automotive equipment. For instance, metal corrosion which is detrimental to reliability of devices is observed in such multi-layered systems during thermal cycles. Therefore, after semiconductor devices have been packaged, a passivation integrity testing (PIT) is performed to assess the liability of the device. During thermal cycle testing, temperature is changed, for example, from −65° C. to 150° C. The PIT includes thermal cycles. For example, 200 X thermal cycles are performed during the PIT. A passivation stack on the pad interconnects is easily destroyed and moisture enters into the inside of the device, causing a failure in the PIT.
The present disclosure relates to providing more reliable pad schemes, which are compatible with the materials of the wire bond and pass the chip package interaction (CPI) qualification requirement, and the methods of manufacturing the same.